Kilims are produced by tightly interweaving the warp and weft strands of the weave to produce a flat surface with no pile. Most kilim weaves are "weft-facing", i.e., the horizontal weft strands are pulled tightly downward so that they hide the vertical warp strands.
When the end of a color boundary is reached, the weft yarn is wound back from the boundary point. Thus, if the boundary of a field is a straight vertical line, a vertical slit forms between the two different color areas where they meet. For this reason, most kilims can be classed as "slit woven" textiles. The slits are beloved by collectors, as they produce very sharp-etched designs, emphasizing the geometry of the weave. Weaving strategies for avoiding slit formation, such as interlocking, produce a more blurred design image.
The weft strands, which carry the visible design and color, are almost always wool, whereas the hidden warp strands can be either wool or cotton. The warp strands are visible only at the ends, where they emerge as the fringe. This fringe is usually tied in bunches, to ensure against loosening or unraveling of the weave.